1. Field of the Invention
The present invention relates to an information processing apparatus equipped with an overwrite deletion function, a method of controlling the same, and a storage medium.
2. Description of the Related Art
Conventionally, there has been known an information processing apparatus that is capable of accumulating information using an external storage device, such as a hard disk drive (hereinafter referred to as the “HDD”). The HDD stores data and position information indicative of locations of the data in the HDD (hereinafter referred to as the “FAT (file allocation table)”).
Further, some information processing apparatuses of this type temporarily store received information (hereinafter referred to as “data”), and delete the data from the HDD after completion of processing (hereinafter referred to as a “job”).
If the HDD is removed from the information processing apparatus in a state where the data is stored in the HDD before being deleted therefrom and is connected to another computer for analyzing the interior of the HDD, there is a danger that the data is stolen from the HDD.
As the awareness of such danger and information security increases, an overwrite deletion function for deleting not only a FAT but also remaining data has come to be widely known.
In an information processing apparatus having the overwrite deletion function, it is guaranteed that there is no remaining data, by writing 0's, random numbers, or fixed values, over used data once or a plurality of times simultaneously with completion of a job.
On the other hand, a technique of hibernation has been proposed which restores the status of a system by storing, in the HDD, system information stored in a volatile area (hereinafter referred to as the “RAM”), reading out the system information from the HDD during the next startup of the system, and writing back the system information in the RAM.
The hibernation is widely known as a technique for restoring the system from a power-off state thereof at a high speed by combining techniques for compressing and reducing the system information. Note that there is a possibility that the system information stored in the HDD during a hibernation period includes information, such as user information and its cache information, which should be deleted by the overwrite deletion function.
Based on the above-described background, a technique has been disclosed which saves secret information from the HDD to a memory before the system shifts to a power saving state, and what is more, causes the secret information stored in the HDD to be overwritten and deleted (see e.g. Japanese Patent Laid-Open Publication No. 2011-005683). This is a technique for simultaneously realizing prevention of leakage of the secret information from the HDD e.g. removed in the power saving state for analysis and holding of the secret information in the memory without any loss thereof.
However, when the overwrite deletion function and the hibernation function are used in combination, the power of the system is sometimes turned off while data to be deleted by the overwrite deletion function is included in the system information. The system information is provided for performing the next startup of the system at a high speed, and when user information is determined and deleted from the system information, it takes extra time to perform a termination process since the determination and deletion of the user information are performed.